Characterizing Disease Burden and Progression of Geographic Atrophy Secondary to Age-Related Macular Degeneration

Abstract

Purpose: To understand levels of disease burden and progression in a real-world setting among patients from the United Kingdom with bilateral geographic atrophy (GA) secondary to age-related macular degeneration (AMD).

Design: Retrospective cohort analysis of a multicenter electronic medical record (EMR) database.

Participants: Patients who were aged ≥50 years with bilateral GA and no history of choroidal neovascularization (CNV) and who attended 1 of 10 clinical sites using the EMR.

Methods: A deidentified data set was constructed from the records held at the 10 sites. An algorithm was used to extract cases with a GA diagnosis, of which 1901 had bilateral GA and form the basis of this report. A sample of records randomly selected from each center was used to validate disease definitions.

Main outcome measures: Progression to blindness (visual acuity [VA] <20 letters or Snellen 3/60 in the better-seeing eye), driving ineligibility (VA ≤70 letters or Snellen 6/12 in the better-seeing eye), progression to CNV, loss of 10 or more letters, and mean change in VA over time.

Results: At first record of GA, 7.1% had a VA in the better-seeing eye equal to or lower than the cutoff for blindness registration and 71.1% had a VA that would have rendered them ineligible to drive. Over time, 16% became legally blind (median time to outcome, 6.2 years) and 66.7% became ineligible to drive (median time to outcome, 1.6 years). In the worse-seeing eye, 40.1% lost ≥10 letters in 2.4 years. Among patients with baseline and 24-month VA measurements, mean VA decline was 6.1 letters in the worse-seeing eye (n = 413) and 12.4 letters in the better-seeing eye (n = 414). The rate of progression to CNV in either eye was 7.4% per patient-year.

Conclusions: At initial diagnosis, based on VA in the better-seeing eye, a high proportion of patients with bilateral GA were ineligible to drive and approximately 7% were eligible for UK blindness registration. The subsequent reduction in VA that occurred in the better-seeing eye would render a further two-thirds ineligible to drive. These findings emphasize the severity of the visual disability associated with GA secondary to AMD.